Add child view controller swift

Question

I m trying to add child view controller to a containerViewController

Child are :

AViewController
BViewController
CViewController

I have no error but when i launch the app, i can swipe the screen, there is 3 section swiped but the A,B,C view controllers don't appeared..

This is my code, any idea ?

import UIKit

class ContainerViewController: UIViewController {

@IBOutlet var scrollView: UIScrollView!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.


    // creat VC

    var Avc : AViewController = AViewController ()
    var Bvc : BViewController = BViewController ()
    var Cvc : CViewController = CViewController ()



    // add it to the view hierarchie


    self.addChildViewController(Cvc)
    self.scrollView.addSubview(Cvc.view)
    Cvc.didMoveToParentViewController(self)

    self.addChildViewController(Bvc)
    self.scrollView.addSubview(Bvc.view)
    Bvc.didMoveToParentViewController(self)


    self.addChildViewController(Avc)
    self.scrollView.addSubview(Avc.view)
    Avc.didMoveToParentViewController(self)

    // set the frame

    var adminFrame : CGRect = Avc.view.frame
    adminFrame.origin.x = adminFrame.width
    Bvc.view.frame = adminFrame

    var BFrame : CGRect = Bvc.view.frame
    BFrame.origin.x = 2*BFrame.width
    Cvc.view.frame = BFrame

    // set the frame of the scrollview


    var scrollWidth: CGFloat = 3*self.view.frame.width
    var scrollHeight: CGFloat = self.view.frame.size.height
    self.scrollView.contentSize = CGSizeMake(scrollWidth, scrollHeight)


}

Edit:

Looking at the view hierarchy, it reports the following:

<UIWindow: 0x7ff3fad19f70; frame = (0 0; 320 568); gestureRecognizers = <NSArray: 0x7ff3fac3efe0>; layer = <UIWindowLayer: 0x7ff3fad19740>>
   | <UIView: 0x7ff3fb108b90; frame = (0 0; 320 568); autoresize = W+H; layer = <CALayer: 0x7ff3fb108e60>>
   |    | <UIScrollView: 0x7ff3fac3acf0; frame = (0 0; 320 568); clipsToBounds = YES; autoresize = RM+BM; gestureRecognizers = <NSArray: 0x7ff3fb107320>; layer = <CALayer: 0x7ff3fac18e00>; contentOffset: {0, 0}; contentSize: {960, 568}>
   |    |    | <UIView: 0x7ff3fac41ed0; frame = (640 0; 320 568); autoresize = W+H; layer = <CALayer: 0x7ff3fac28a00>>
   |    |    | <UIView: 0x7ff3fac42320; frame = (320 0; 320 568); autoresize = W+H; layer = <CALayer: 0x7ff3fac38e10>>
   |    |    | <UIView: 0x7ff3fac42730; frame = (0 0; 320 568); autoresize = W+H; layer = <CALayer: 0x7ff3fac42810>>
   |    |    | <UIImageView: 0x7ff3faf020f0; frame = (0 564.5; 320 3.5); alpha = 0; opaque = NO; autoresize = TM; userInteractionEnabled = NO; layer = <CALayer: 0x7ff3fae0df80>>
   |    |    | <UIImageView: 0x7ff3fac1c660; frame = (316.5 0; 3.5 568); alpha = 0; opaque = NO; autoresize = LM; userInteractionEnabled = NO; layer = <CALayer: 0x7ff3fac39420>>
   |    | <_UILayoutGuide: 0x7ff3fb108ec0; frame = (0 0; 0 20); hidden = YES; layer = <CALayer: 0x7ff3fb1091e0>>
   |    | <_UILayoutGuide: 0x7ff3fb109c20; frame = (0 568; 0 0); hidden = YES; layer = <CALayer: 0x7ff3fb109d00>>

Answer 1

Use following Extension for adding ChildviewController create file Extensions.swift copy bellow code

import UIKit

extension UIViewController {
    func configureChildViewController(childController: UIViewController, onView: UIView?) {
        var holderView = self.view
        if let onView = onView {
            holderView = onView
        }
        addChildViewController(childController)
        holderView?.addSubview(childController.view)
        constrainViewEqual(holderView: holderView!, view: childController.view)
        childController.didMove(toParentViewController: self)
    }


    func constrainViewEqual(holderView: UIView, view: UIView) {
        view.translatesAutoresizingMaskIntoConstraints = false
        //pin 100 points from the top of the super
        let pinTop = NSLayoutConstraint(item: view, attribute: .top, relatedBy: .equal,
                                    toItem: holderView, attribute: .top, multiplier: 1.0, constant: 0)
        let pinBottom = NSLayoutConstraint(item: view, attribute: .bottom, relatedBy: .equal,
                                       toItem: holderView, attribute: .bottom, multiplier: 1.0, constant: 0)
        let pinLeft = NSLayoutConstraint(item: view, attribute: .left, relatedBy: .equal,
                                     toItem: holderView, attribute: .left, multiplier: 1.0, constant: 0)
        let pinRight = NSLayoutConstraint(item: view, attribute: .right, relatedBy: .equal,
                                      toItem: holderView, attribute: .right, multiplier: 1.0, constant: 0)

        holderView.addConstraints([pinTop, pinBottom, pinLeft, pinRight])
    }
}

User view controller

    import UIKit

    class MyViewControler:UIViewControler  {

    @IBOutlet weak var myView: UIView!



    override func viewDidLoad() {
        super.viewDidLoad()

        let demoViewInstance = storyboard!.instantiateViewController(withIdentifier: "youChiledViewController_Id") as! childViewController
        configureChildViewController(childController: demoViewInstance, onView: myView)

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

Answer 2

When I use your code, run the app, and pause the app, and look at the view hierarchy, I see the following:

(lldb) po [[UIWindow keyWindow] recursiveDescription]
<UIWindow: 0x156bdc30; frame = (0 0; 320 568); gestureRecognizers = <NSArray: 0x156be750>; layer = <UIWindowLayer: 0x156aa3c0>>
   | <UIView: 0x156c5440; frame = (0 0; 320 568); autoresize = W+H; layer = <CALayer: 0x156c55c0>>
   |    | <UIScrollView: 0x156c2740; frame = (0 0; 0 568); clipsToBounds = YES; autoresize = RM+BM; gestureRecognizers = <NSArray: 0x156c4d00>; layer = <CALayer: 0x156c2a80>; contentOffset: {0, 0}; contentSize: {960, 568}>
   |    |    | <UIView: 0x156c6df0; frame = (640 0; 0 536); autoresize = W+H; layer = <CALayer: 0x156c6d80>>
   |    |    | <UIView: 0x156c7100; frame = (320 0; 0 536); autoresize = W+H; layer = <CALayer: 0x156c70a0>>
   |    |    | <UIView: 0x156c73f0; frame = (0 0; 0 536); autoresize = W+H; layer = <CALayer: 0x156c7390>>
   |    |    | <UIImageView: 0x156c8bd0; frame = (0 564.5; 600 3.5); alpha = 0; opaque = NO; autoresize = TM; userInteractionEnabled = NO; layer = <CALayer: 0x156c8c50>>
   |    |    | <UIImageView: 0x156c9020; frame = (-3.5 32; 3.5 568); alpha = 0; opaque = NO; autoresize = LM; userInteractionEnabled = NO; layer = <CALayer: 0x156c90a0>>
   |    | <_UILayoutGuide: 0x156c5620; frame = (0 0; 0 20); hidden = YES; layer = <CALayer: 0x156c5800>>
   |    | <_UILayoutGuide: 0x156c5c90; frame = (0 568; 0 0); hidden = YES; layer = <CALayer: 0x156c5d10>>

If you're not seeing your subviews there, then likely culprits include:

• You may not have specified the view controller base class in your scene, and thus this code isn't being run. You can confirm this with a println log statement or breakpoint in side this viewDidLoad and make sure you're hitting this routine.

• You may not have hooked up the @IBOutlet for the scrollView , and thus scrollView is nil . Confirm this by putting breakpoint in viewDidLoad and examining the scrollView property.

---

In your revised question, we can now see that the three subviews are present and appear to be the correct size. That's great.

Now the question is why you don't see anything. If you have these defined as scenes in your storyboard, you should:

• Make sure the "base class" and the "storyboard identifier" is defined for each of these three child scenes; and

• When your main view controller instantiates the three child view controllers, you would instantiate them from the storyboard using the storyboard identifier (in my example, I used storyboard identifiers of A , B , and C , respectively):

   let Avc = storyboard.instantiateViewControllerWithIdentifier("A") as AViewController let Bvc = storyboard.instantiateViewControllerWithIdentifier("B") as BViewController let Cvc = storyboard.instantiateViewControllerWithIdentifier("C") as CViewController 

If you do the above and repeat the recursiveDescription you should see your scene's subviews (eg the labels you added) appear in the output.